By way of background, a variety of beverage brewing machines have been developed. Many of these brewers include a heated water reservoir in which water is introduced to the reservoir for heating and retained in the reservoir until it is necessary to dispense. Water is dispensed from the reservoir typically at an upper end so that the most heated water retained in the reservoir is dispensed first. A dispensed tube is connected to the reservoir at one end and a spray head at an opposite end. Water flows into the reservoir generally through a lower portion of the reservoir and displaces water therein for dispensing through the spray tube. Typically the water flow continues until water ceases to enter the reservoir. At this point the dispense tube drains out and the brewing cycle is completed.
One of the methods for controlling outlet from the reservoir is the use of a control valve communicating with the dispense tube. A complication with such control valves that it may be subjected to clogging or other complications as a result of lime build up. Lime build up occurs as minerals such as lime precipitate or evaporate out of the water in the reservoir. This process is enhanced by the heating of the water in the reservoir. The accumulation of lime is detrimental such that it can block or at least slow down the flow of water from the reservoir to the spray head. In order to try to eliminate this complication periodic cleaning of the dispense tube is required to remove the lime.